JPH08277795A - Centrifugal pump - Google Patents

Abstract

PURPOSE: To provide a pump in which having no need to change pump parts and having the long life, by rotating an impeller with no contact through a process of restraining the movement of an impeller in the thrust direction in the high-speed rotation of the impeller in a centrifugal pump for transmitting power by magnetic connection. CONSTITUTION: A centrifugal pump is provided with a rotating body 5 to be rotated and driven by a motor 2 and provided with a first magnet 4, and an impeller 8 provided with a second magnet 7 to be magnetically connected to the magnet 4 of this rotating body 5, and to be rotated in a pump chamber 18. In the impeller 8, a through hole 10 is partially provided on a blade 9, and the impeller 8 is restrained from being moved in the thrust direction caused by negative pressure of the pump chamber 18, to be generated by the rotation of the impeller 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal pump which is magnetically coupled to transmit power.

[0002]

2. Description of the Related Art As a conventional centrifugal pump of this type, a structure shown in FIG. 7 is known. This is provided with a rotating body 28 having a first magnet 27 on the inner periphery of a shaft 26 of a motor 25, and a second magnet which is opposed to and magnetically coupled to the first magnet 27 via a partition wall of a pump case 29.
The impeller 31 having the magnet 30 of the
Is inserted and fixed between the shaft support portions 34 and 35 of the pump cases 29 and 33. A spacer 37 is provided between the bearing 36 to which the impeller 31 is attached and the shaft support portion 34 of the pump case 29. When the impeller 31 rotates, one end of the bearing 36 slides on the spacer 37 to rotate. are doing.

8 and 9 show the structure of the impeller 31, the bearing 36 is generally formed by molding, and the shaft hole 36a for receiving the shaft 32 is formed at the time of molding as shown in FIG. The bearing 30 is provided with the magnet 30 on the outer periphery thereof, and the blade 3 of the impeller 31 is provided.
A blade 39 is provided on the surface 8.

In such a structure, in order to pump up the liquid, the magnetically coupled impeller 31 is driven to rotate by the rotation of the motor 25, and the liquid flows from the suction port 40 at the center of the pump case 29 to the blades of the impeller 31. It is pressurized by a centrifugal force by 39 and is pushed out through a discharge port 41 provided on the outer circumference of the pump case 29.

The operation of the pump case 2 will be described in detail.
When the impeller 31 rotates at a high speed in a state where the pump chamber 42 constituted by 9 and 33 is filled with the liquid, the liquid is stirred by the blades 39 to give energy, and the liquid flows toward the outer periphery by the centrifugal force and the discharge port. Discharge from 41. In this case, the filled liquid in the central portion is discharged to the outside, so that the pressure in the central portion is reduced and the liquid in the suction port 40 is sucked by the atmospheric pressure. By such an operation,
When the impeller 31 rotates at a high speed, the inside of the pump chamber 42 is in a negative pressure state, receives a force from the back surface of the blade 38 of the impeller 31, and in the state shown in the figure, the impeller 31 floats upward, and the bearing 36 and the spacer 37 of the impeller 31. And slide and rotate.

[0006]

Therefore, when the above-mentioned conventional centrifugal pump is operated for a certain period of time, it is necessary to replace the spacer 37 and the entire shaft 32 or the impeller 31 as a consumable item. Next, regarding the relationship between the shaft 32 and the bearing 36, the gap between the shaft 32 and the bearing 36 is provided with a certain clearance, but the shaft 26 of the motor 25 is
Since the bearing 36 of the impeller 31 magnetically coupled to the shaft 32 acts as a sliding resistance according to the amount of eccentricity of the shaft 32 due to the eccentricity of the rotating body 28 from the above, when there is no liquid in the pump chamber 42, that is, the lubricating liquid When it does not exist, the sliding noise is large, and when the material of the bearing 36 is resin, the resin melts, so that it cannot be operated without liquid and cannot be used in idle operation. That is, in such a configuration, there is a problem that the pump parts need to be replaced when used for a certain period of time and cannot be used in idle operation.

Therefore, the present invention solves these problems and suppresses the movement of the impeller in the thrust direction even when the impeller rotates at a high speed, rotates the impeller without contact, and requires no replacement of pump parts. It is a primary object to provide a centrifugal pump with a long life.

A second object is to allow the eccentric amount of the rotating body fixed to the shaft of the motor to be absorbed by the shaft supporting structure of the impeller so that the pump can be idle.

A third object is to make the bearing member of the impeller common and to improve the dimensional accuracy of the parts so as to reduce the noise and prolong the life of the pump.

A fourth object is to facilitate the supply of the lubricating liquid to the bearing portion of the impeller to extend the life of the pump.

Further, the arrangement of magnetic coupling suppresses the movement of the impeller in the thrust direction during high-speed rotation of the impeller, rotates the impeller without contact, and provides a long-life pump without replacement of pump parts. The fifth purpose.

[0012]

A first aspect of the present invention for achieving the above-mentioned first object is to rotate and drive a first motor.
A rotating body having a magnet, and an impeller having a second magnet that is magnetically coupled to the magnet of the rotating body and rotating in the pump chamber. The impeller has a part of its blade in the thrust direction of the impeller. The centrifugal pump is provided with a movement suppressing portion that suppresses movement. Further, the movement suppressing portion provided on the blade of the impeller has a through hole,
Notches or slits are used.

A second invention for achieving the second object has a rotating body which is driven to rotate by a motor and has a first magnet, and a second magnet which is magnetically coupled to the magnet of the rotating body. An impeller rotating in a pump chamber, the impeller being rotatably supported by a support shaft supported by a shaft support portion, and the support shaft being a centrifugal pump movable in a radial direction with respect to the shaft support portion. It is a thing. The shaft hole diameter of the shaft support portion is larger than the shaft diameter of the support shaft.

A third invention for achieving the third object has a rotating body which is rotationally driven by a motor and has a first magnet, and a second magnet which is magnetically coupled to the magnet of the rotating body. The bearing that includes an impeller that rotates in the pump chamber and that rotatably supports the impeller is a centrifugal pump that is configured by symmetrically combining two bearing members of the same shape.

A fourth invention for achieving the fourth object is a centrifugal pump in which a lubricating liquid reservoir is provided in an intermediate portion of a bearing for rotatably supporting an impeller.

A fifth invention for achieving the fifth object has a rotating body which is rotationally driven by a motor and has a first magnet, and a second magnet which is magnetically coupled to the magnet of the rotating body. A centrifugal pump having an impeller rotating in a pump chamber, wherein the first and second magnets are magnetically coupled to each other on an outer circumference of the impeller, and the first magnet is installed so as to be displaced from the second magnet toward a motor side. It is what

[0017]

According to the first aspect of the present invention, when the impeller rotates at a high speed in a state where the pump chamber is filled with the liquid, the liquid is stirred by the impeller to give energy, and flows toward the outer periphery by centrifugal force. In this case, the filled liquid in the central portion is discharged to the outside, so that the pressure in the central portion is reduced and the liquid on the suction side is sucked by the pressure of the atmosphere. By such an operation, when the impeller rotates at high speed, even if the pump chamber is in a negative pressure state, the impeller has a movement restraining part, so that it does not receive the force from the back surface, and even when the impeller rotates at high speed, the impeller thrust direction is increased. The movement of
The impeller can be rotated without contact, and there is no need to replace pump parts. The movement suppressing portion is a through hole, a notch or a slit, and can easily release the back pressure of the impeller.

Further, according to the second aspect of the invention, since the support shaft is movable in the radial direction with respect to the shaft support portion, the eccentricity of the rotating body causes the magnetically coupled impeller to move and rotate according to the amount of eccentricity. Can absorb the amount of eccentricity of the body,
It can be operated even when there is no liquid in the pump chamber.
Further, this is made possible by making the shaft hole diameter of the shaft support portion larger than the shaft diameter of the support shaft.

According to the third aspect of the invention, the bearing for rotatably supporting the impeller is formed by symmetrically arranging two bearing members of the same shape, so that the length of one bearing member can be shortened. In addition, the draft which occurs during the molding process is not required, the dimensional accuracy of the parts is improved, the bearing member of the impeller is shared, and the noise of the pump and the life of the pump can be increased.

According to the fourth aspect of the present invention, since the lubricating liquid reservoir is provided in the intermediate portion of the bearing that rotatably supports the impeller, the lubricating liquid can be retained through the clearance between the support shaft and the bearing. It is possible to prevent wear of the bearing.

According to the fifth aspect of the invention, the first and second magnets are magnetically coupled to each other on the outer circumference of the impeller, and the first magnet is installed so as to be displaced from the second magnet on the motor side. The impeller is attracted to the motor side, and even when the impeller rotates at high speed, the impeller is prevented from moving in the thrust direction and can be rotated without contact.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In FIGS. 1 and 2, reference numeral 1 denotes a motor case, to which a motor 2 is fixed, and a rotor 5 having a motor shaft 2a and a first magnet 4 provided on an inner circumference thereof via a joint 3.
In addition, there is an impeller 8 having a second magnet 7 that is magnetically coupled to the magnet 4 so as to face each other through a partition wall of the pump case 6. The blade 9 of this impeller 8 has a diameter of 28 mm, and as shown in FIGS.
Each 6 mm through hole 10 is provided. Although the number of the through holes 10 is not particularly limited, it constitutes a movement suppressing portion for suppressing the movement of the impeller 8 in the thrust direction, and notches or slits are formed in the blade 9 instead of the through holes. Etc. may be provided and configured. The blade 9 is provided with a plurality of blades 9a.

The impeller 8 is integrally provided with a bearing 11 formed by symmetrically combining two bearing members 11a and 11b having the same shape as shown in FIG. This bearing 1
The hole diameter of the portion of the bearing 1 that contacts the support shaft 12 is 3.03 mm, and in the middle of the bearing 11, it is 4 mm larger than the diameter of the support shaft 12.
To form a reservoir 13 for the lubricating liquid. In addition, FIG.
As shown in, the diameter of the support shaft 12 is 3 mm,
Shaft support part 1 provided in the center of pump case 14 for supporting
The shaft hole diameter of 5 is 3.5 mm, and the shaft hole diameter of the shaft support portion 16 provided in the center of the pump case 6 is 3.5 mm, which is considerably larger than the shaft diameter of the support shaft 12, and the support shaft 12 moves in the radial direction. It is possible.

The arrangement of the magnet 7 of the impeller 8 and the magnet 4 of the rotating body 5 is such that the magnet 4 is displaced toward the motor 2 by t (1.5 mm).

In the figure, 17 is a packing, which is located between the pump cases 6 and 14, and is fixed by screwing the pump case 14 and the motor case 1 to each other.
A watertight pump chamber 18 is formed by 14. Also,
At the same time, a space between the pump case 6 and the motor case 1 also becomes a sealed space, in which the rotating body 5 is located. A suction port 19 is provided at the center of the pump case 14, and a discharge port 2 is provided at the outer periphery.
0 is provided, and the liquid is sucked through the suction port 19 and discharged through the discharge port 20.

The operation will be described below. In order to pump the liquid, the impeller 8 magnetically coupled is driven to rotate by the rotation of the motor 2, and the liquid is centrifugally pressurized from the suction port 19 at the center of the pump case 14 by the blades 9a of the impeller 8 to pump the liquid. It is pushed out from the discharge port 20 provided on the outer periphery of the case 14.

This operation will be described in detail. When the impeller 8 rotates at a high speed in a state where the pump chamber 18 is filled with the liquid, the liquid is stirred by the blades 9a to be given energy and flows toward the outer periphery by the centrifugal force. , Through the discharge port 20. In this case, the filled liquid in the central portion is discharged to the outside, so that the pressure in the central portion is reduced and the liquid in the suction port 19 is sucked by the atmospheric pressure. When the impeller 8 rotates at high speed, the pump chamber 18 becomes a negative pressure state, and the impeller 8
In the state shown in the drawing, a force acts to lift the impeller 8 upward in response to a force from the back surface of the blade 9 of the blade 9 of FIG. The force applied is reduced, and the magnet 7 and the magnet 4 attract each other to rotate in a state of being lifted up by about 1.5 mm.

In the structure according to this embodiment, the rotation speed of the impeller 8 is 2000 r / min, but the diameter of the through hole 10 and the positional relationship of the magnet 4 can be set to an optimum state depending on the rotation speed. Therefore, the bearing 11 of the impeller 8 has no contact point in the thrust direction, and the impeller 8 rotates while floating in the air, so that there is no wear in the thrust direction. On the other hand, regarding the wear in the radial direction, the support shaft 12
Although a constant clearance is provided between the bearing 11 and the bearing 11, the bearing 11 of the impeller 8 magnetically coupled to the support shaft 12 by the eccentricity of the rotating body 5 from the motor shaft 2a Acts as sliding resistance, but shaft support 1
By considering the relationship between the shaft hole diameters of 5 and 16 and the shaft diameter of the support shaft 12, the support shaft 1 can be adjusted according to the eccentricity of the rotating body 5.
2 can move in the radial direction, and the amount of eccentricity of the rotor 5 from the motor shaft 2a can be absorbed. Therefore, no sliding noise is generated even when there is no liquid in the pump chamber 18, that is, when no lubricating liquid exists.
With such a structure, the impeller 8 has no sliding portion, and therefore, a pump having a long life can be obtained without any replacement of parts.

The centrifugal pump can be used, for example, for pumping hot water or cooling water in a jar pot used at home or for circulation.

[0030]

As described above, according to the centrifugal pump of the first aspect of the present invention, the movement suppressing portion is provided in a part of the blade of the impeller, so that the movement of the impeller in the thrust direction is suppressed even when the impeller rotates at high speed. Since the impeller can be rotated without contact, it is not necessary to replace pump parts, and a pump with a long life can be provided.

According to the second aspect of the invention, since the support shaft is movable in the radial direction, the bearing of the impeller magnetically coupled to the support shaft is eccentric due to the eccentricity of the rotor from the motor shaft. Since the eccentric amount of the rotating body can be absorbed by moving according to the amount, the pump can be operated even when there is no liquid in the pump chamber, that is, when there is no lubricating liquid.

According to the third aspect of the invention, since the bearings of the impeller are constructed by symmetrically combining two bearing members of the same shape, the length of the bearing member can be shortened, and the bearing like an integral type bearing can be obtained. The dimensional accuracy of parts is improved without the need for a draft when molding is performed, and the dimensional accuracy of parts is improved by sharing the bearing members of the impeller, which results in quieter pumps and longer service life. You can

According to the fourth aspect of the invention, since the lubricating liquid can be accumulated through the clearance between the support shaft and the bearing by providing the liquid reservoir in the middle part of the bearing, the lubricating liquid is constantly kept in the bearing. It is full and is easily supplied to the bearing, and it is possible to prevent wear of the bearing.

According to the fifth aspect of the invention, since the magnet of the rotating body is set to be displaced from the magnet of the impeller on the motor side, the impeller is attracted to the motor side, and the impeller is rotated even at a high speed. It is possible to rotate the impeller without contact by suppressing the movement in the thrust direction.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a centrifugal pump according to an embodiment of the present invention.

FIG. 2 is a plan view of the centrifugal pump.

FIG. 3 is a plan view showing an impeller of the centrifugal pump.

FIG. 4 is a vertical sectional view of the impeller.

FIG. 5 is a vertical sectional view showing a bearing of the impeller.

FIG. 6 is a vertical cross-sectional view showing the relationship between the impeller, the support shaft, and the bearing.

FIG. 7 is a vertical sectional view showing a conventional centrifugal pump.

FIG. 8 is a plan view showing an impeller of the centrifugal pump.

FIG. 9 is a vertical sectional view of the impeller.

FIG. 10 is a vertical sectional view showing a bearing of the impeller.

[Explanation of symbols]

 4 Magnet 5 Rotating Body 6 Pump Case 7 Magnet 8 Impeller 10 Through Hole 11 Bearing 12 Support Shaft 13 Reservoir 14 and 16 Shaft Support

Claims (7)

[Claims] 1. A rotary body driven to rotate by a motor and having a first magnet, and an impeller having a second magnet magnetically coupled to the magnet of the rotary body and rotating in a pump chamber, wherein the impeller comprises: A centrifugal pump in which a movement suppressing portion that suppresses the movement of the impeller in the thrust direction is provided in a part of the blade. 2. The centrifugal pump according to claim 1, wherein the movement suppressing portion provided on the blade of the impeller is a through hole, a notch or a slit. 3. A rotating body driven by a motor to have a first magnet, and an impeller having a second magnet magnetically coupled to the magnet of the rotating body and rotating in a pump chamber, wherein the impeller is provided. A centrifugal pump rotatably supported by a support shaft supported by a shaft support portion, the support shaft being movable in a radial direction with respect to the shaft support portion. 4. The centrifugal pump according to claim 3, wherein the shaft hole diameter of the shaft support portion is larger than the shaft diameter of the support shaft. 5. A rotor including a first magnet, which is rotationally driven by a motor, and an impeller, which has a second magnet magnetically coupled to the magnet of the rotor, and rotates in a pump chamber. The bearing that is rotatably supported is a centrifugal pump that is configured by symmetrically combining two bearing members of the same shape. 6. The centrifugal pump according to claim 5, wherein a lubricating liquid reservoir is provided at an intermediate portion of the bearing. 7. A rotating body driven by a motor and having a first magnet, and an impeller having a second magnet magnetically coupled to the magnet of the rotating body and rotating in a pump chamber. A centrifugal pump in which the first magnet and the second magnet are magnetically coupled to each other on the outer circumference of the impeller, and the first magnet is displaced from the second magnet on the motor side.